The great 19th century Russian playwright Anton Chekhov said it was a rule of the theatrical stage: If a loaded gun appears in the first act, that gun will be fired before the curtain falls. It's a rule of the world stage as well: If rogue states such as North Korea and Iran obtain weapons of mass destruction, we must expect those weapons will be used eventually, with all the death and destruction that implies.

For this reason, preventing the proliferation of nuclear weapons to extreme and irresponsible regimes has long been a priority for American leaders of both political parties. But an effective strategy for keeping such weapons out of despots' clutches has proved elusive.

In 1994, the Clinton administration sat down with North Korean diplomats and cut a deal: The U.S. would provide billions of dollars worth of aid -- massive amounts of food, fuel oil and even two energy-producing nuclear power plants -- in exchange for a promise from Pyongyang to halt nuclear weapons production.

Clinton trusted but did not verify. The North Korean regime was cheating on the deal “before the ink was dry,” in the words of John Bolton, U.S Ambassador to the U.N.

The Bush administration has tried a different approach: multi-lateral diplomacy, endless talks with no one saying anything very persuasive to Kim Jong Il, the vicious and eccentric dictator who has made North Korea into a living hell for most of its citizens.

So what's next? Many Bush critics are, ironically, calling for Bush to go it alone: to agree to another round of direct talks between American and North Korean diplomats. That begs the question: What would we say in such a tête-à-tête? What would be offered? What would be threatened? Without good answers, negotiations can not be productive.

Sanctions against North Korea -- under the auspices of the United Nations -- is the route the Bush administration is now pursuing. To have teeth, they need to include a strict embargo on all military hardware and authorization both to search ships going to and from North Korea and to seize any illicit cargo discovered. That could prevent North Korea from exporting nuclear weapons to terrorists – a useful outcome. But it doesn't go far enough.

What else is necessary? For China to use its considerable leverage to thwart Kim's ambition to head a nuclear-armed state – something it should have done long ago. To persuade China to do the right thing now will require not just diplomatic efforts but diplomatic pressure.

For example, it should be made clear to China's leaders that if they won't stand in the way of a nuclear North Korea, we won't stand in the way of a nuclear Japan – on the contrary, we will strongly encourage such a development. And perhaps Taiwan, too, might be assisted along this path. Free and democratic countries, we should explain, have the right to deter and defend themselves from dictatorships with hostile intentions and escalating capabilities.

China's leaders also should be informed that Washington will consider what steps might be taken to push the North Korean regime closer to the collapse it so richly deserves. If that happens, Chinese officials will have a huge refugee crisis to cope with, as well as an opportunity to try their hands at “nation-building.”

The 2008 Olympics should be in play. China is hosting the games. They will be less than a smashing success if athletes from the United States and its allies decline to attend.

Lastly, we should remind China that the vibrant economic growth it has experienced in recent years has depended largely on its access to American markets. That, too, will be in jeopardy if China refuses to cooperate. European nations might put principle over profits, too – unlikely but not unimaginable.

On more than one occasion, President Bush has said that the world's worst dictators must not be permitted to acquire the world's most dangerous weapons. On this issue if no other Bush deserves bipartisan support.

It must be demonstrated to China's leaders that Americans are serious about not letting rogue regimes acquire nuclear weapons. Iran's rulers also need to see that there are limits beyond which Americans will not be pushed.

The alternative is for maniacs and tyrants to soon be strutting the world stage waving nuclear weapons at us. Based on Chekhov or just common sense, we should have no illusions about how such dramas end.